Klosjukdomar hos hund : en litteraturstudie och en fallstudie i den Svenska Riesenschnauzerpopulationen

Sammanfattning: Various problems with nail disorders have been noticed in the Swedish population of Giant Schnauzer, but the frequencies of these problems are unknown. This could be due to the fact that bad nail quality has several differential diagnoses and lack of diagnostic criteria and diagnostic codes for nail disorders. The main purpose of this study is to review different types of claw defects and diseases of the nail bed in dogs, and to classify and evaluate the proportions in the Swedish Giant Schnauzer population. The nail is a specialized part of the skin. The quick will strengthen and protect the third phalang against the surrounding. Many different defects in the claw matrix in dogs are described in the literature. The defects can be divided after the clinical spreading (symmetrical or asymmetrical) or in specific diseases and claw defects without specific state of disease. There are few specific nail diseases and histological evaluation of the nail bed is always needed for a correct diagnosis. Symmetrical lupoid onychodystrophy is the definition for a symmetrical claw capsule loosening where specific changes in the nail bed can be present in the histological evaluation. The most common tumours in the nail bed are squamous cell carcinomas and malign melanomas. Also these diseases are diagnosed based on histological evaluation. Defects in the claw without any specific nail disease are more common than specific diseases in nail bed. Trauma is most common cause of claw capsule fracture in dogs. The etiology for other claw defects as paronychia, onychomadesis, onychorrhexis and onychodystrofi can vary. Nail quality can be affected by a many different factors, i.e. age and nutrition. Other reasons of poor nail quality and nail diseases are immunomediated and endocrine disorders, which can predispose for secondary infections in the nail bed. The study shows that at least 8% of the Swedish Giant schnauzer population are at risk to contract recurrent nail problems and at least 3,2% of the population at risk to contract serious diseases in the nail matrix. Hypothyreosis, wich in the literature have been proposed to predispose for impaired nail quality, seems not to be more common in Giant schnauzers with nail disorders than in the rest of the Swedish breed population and treatment for hypothyreosis has not improved the quality of the nails in these dogs. The risk for developing defects in the nail bed has a familiar bound. An increased inbreeding was noted in affected dogs. In the study two families are overrepresented and together they account for more than one forth of all nail problems in the study. One family mostly have problems with more serious nail diseases like tumours and onychomadesis, whereas the other one mostly have problem with a bad nail quality and recurrent claw capsule fragmentation. The results indicate a correlation between different nail diseases – which never earlier have been described in the literature. More studies are needed to evaluate the presence and origin of different claw diseases and defects related to the nail matrix in dog.